Die structure



E. I. I.. GRANLOW.

DIE STRUCTURE.

APPLICATION FILED JUNE 3,192I. Y 19428;???3 Patendsept. 12,1922.,

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Patented Sept. l2,

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ERIC J. L. GRANLOW, 0F SCHENECTADY, YORK.

DIE STRUCTURE.

i Application filed .Tune 3,

To all whom it may concern: c

Be it known that I, Emo J. L. GRANLow, a subject of the King of Sweden, residing at Schenectady,county of SClieneCtady,State of `New York, lhave invented certain new and useful Improvements in Die Structures, of which the following is a specification.

'Ihe present invention relates to dies such as are used with punch presses for punching out or forming small articles from strips or plates of sheet material and has for its object to provide an improved structure and arrangement of vdies for performing certain operations to produce articles of a certain t pe.

yFor a. consideration of what I believe to lbe novel and my invention, attention is directed to the accompanying,description and the yclaims appended thereto.

lIn the drawing, Fig. 1 is a vertical, `sectional view through upper and lower die structures embodying my invention; Figs. 2 and 3 show successive steps or operations performed by the die structure; Fig. 4 shows al completed article of which the structure shown in Fig. 3 forms an element, and Fig. 5 shows a modified structure of upper die.

@ne application of my invention is to form an element used in making what is known as the French type of gasket for spark plugs and the invention is particularly illustrated and described in this connection although it is not necessarily limited thereto.

Referring to Fig. 4' of the drawing, it will be seen that a completed gasket comprises a. ring 5 of suitable metal such as copper which ring is U-shaped in cross-section, the open sideof the U'being on the outside of the ring, and held in the groove yformed between the two legs ofthe U is a washer 6 which may be made of asbestos or other suitable material. In forming gaskets of this character a piece of flat stock such as a strip or sheet of copper of suitable thickness is taken and from this strip or sheet la ring is cut and struck or drawn up in the center to form a round cup-shaped member 7 with a flange 8 around its edge as shown "in Fig. 2. The 'end of this cup is then cut out to provide a short cylinder 9 having a flange 10. After the member or 1921. Serial No. 474,860.

element shown in Fig. 8 has been formed, the washer 6 is placed over cylinder 9 and against flange 10 after which thecylinder .is turned out to complete the gasket as shown in Fig. 4.

More particularly the object of my invention is to provide a new and improved die ,structure which at a single operation will form from flat stock an element as shown in Fig. 3, the die structure first forming a structure as shown in Fig. 2 and then cutting the bottom out of the cup-shaped part 7. This sequence of operations is essential `particularly in gaskets of small size since in .order to obtain accurate dimensions it is desirable to strike or draw the' cup "shaped `member lbefore cutting out the bottom.

I Referring now toFig. 1 wherein I have shown my vimproved die structure, .A indicates the lower die structure which is stationary and B the upper diestructure. which is movable.

' ,The lower die structure comprises la sho 14 which is adapted'to be fastened to` the bed .plate of a punch press of usual construction. At the center of yshoe 14 isa hole 15 counterbored to form a recess 16 in which is located a holderl? having `a central opening 18 counterbored to provide an annular shoulder 19. Projecting from the holder 17 is a threaded flange 20 `against the end of which is fixed an outer diey member21, the same being held in place' by a flanged nut 22 whichv threads onto the .end of flange 20. vLocated in the counterbored portion of opening 18 and resting against annular shoulder 19 is a head 23 from which projects an inner die member 24 located centrally of outer die member 21. Inner die member 24 is a solid post and is held in position by a fstudv 25 which projects down through openings 18 and 15 and has ya nut 26 on its 'end which screws up against the bottom of shoe 14. Located in the annular space between die members 21 and 24 is an ejector ring 27 having a head 28 with which engages the upper ends' of a number of ejector pin 29, three for example. Ejector pins 29 extend down through openings in holder 17 land shoe 14 and .at their lower endsengage a plate 30 against the under side of In Fig. 5, I have shown a modified form of upper die structure which in many respects is similar to that shown in Fig. 1 and corresponding reference numerals with the exponent a added'are used to designate corresponding parts. In the Fig. 5 arrangement, the inner die member 37@L is formed separate from holder 35a, instead of integral therewith as in Fig. 1, and is fastened thereto by a set screw 60. This arrangement enables the die member to be renewed without making a new holder also. The outer die member 43 threads into holder 35a as indicated at 61 and by turning the holder and outer die member relatively to each other the distance between the cutting edge of inner die member 37, ie., its lower end, and the lower end of outer die member 4:3a can be accurately adjusted. Holder 35a is split longitudinally as shown at 62 and when the holder is clamped in the punch press outer die member 43a will be tightly gripped in the holder and held in its correct, adjusted position. In this arrangement flange 50a which carries stripper plate 53a is formed separate from die member L13EL and is fastened in place by a set screw 63. Surrounding pins 52a of which there may be three, for example, equally spaced, are springs 611 which act to hold the stripper plate in the position shown in the drawj ing and assist in returning it to such position when during the operation of the die it is pushed up on die member 43a. In Fig. 1 the stripper plate 53 is returned by its weight alone while in Fig. 5 the stripper plate 53*1 is returned by its weight assisted by springs 64.

The operation of die member as shown in Fig. 5 is the same as that of Fig. 1. The die structure itself however is somewhat simpler and has the advantage that the die members 37il and 13a can be renewed more easily and cheaply.

It will be understood that a die structure embodying my invention may be used to provide elements of shapes other than that shown in Fig. 3 by varying the shape or arrangement of the forming surfaces.

In accordance with the provisions of the patent statutes, I have described the principle of operation of my invention, together with the apparatus which I now consider to represent the best embodiment thereof, but I desire to have is understood that the apparatus shown s only illustrative and that the invention may be carried out by other means.

l/Vhat I claim as new and desire to secure by Letters Patent of the United States, is

1. In combination, a die structure comprising two spaced concentric die members and a second die structure having two concentric die members one of which has a forming surface and the other a cutting edge located behind said forming surface, said die members co-operating to' first strike up a cup-shaped protuberance from a sheet of material and then cut the bottom from the protuberance.

2. In combination, a die structure comprising two spaced concentric die members and a second die structure having die means which is adapted to enter the annular space between the two spaced die members, said die means having an outer cutting edge, a forming surface and an inner cutting edge spaced beyond said forming surface in an axial direction.

3. In combination, a die structure which presents two spaced concentric cutting edges and a second die structure having a part adapted to pass between spaced cutting edges and having cutting edges for cooperation therewith, the cutting edges on said part being spaced one axially beyond the other, said die structures having co-operating forming surfaces.

4.-. In a die structure, a die element having an outer cutting edge, a forming surface which extends axially beyond said cutting edge, and an inner cutting edge located axially beyond said forming surface.

5. In a die structure, an inner die member having an inner cutting edge and an outer die member fixed on the inner die member and having an outer cutting edge and a forming surface both in advance of the inner die member as regards the movement ofthe die structure.

6. In a die structure, an inner die mem ber having an inner cutting edge, an outer die member adjustable axially with respect to the inner die member, said outer die member having a cutting edge and a forming surface, and means for locking said die members in fixed position relatively to each other.

In witness whereof, I have hereunto set my hand this 31st day of May, 1921.

ERIC J. L. GRANLOW. In presence of:-

WM. A. FRIEDMAN. 

